diff --git a/SabreTools.Serialization/Models/NES/Header2.cs b/SabreTools.Serialization/Models/NES/Header2.cs
index 782e2401..53324c4d 100644
--- a/SabreTools.Serialization/Models/NES/Header2.cs
+++ b/SabreTools.Serialization/Models/NES/Header2.cs
@@ -8,49 +8,93 @@ namespace SabreTools.Data.Models.NES
     {
         // All common header parts take up bytes 0-7
 
-        /// <summary>
-        /// Mapper MSB/Submapper
-        /// </summary>
-        /// <remarks>
-        /// Bits 0-3 - Mapper number bits 8-11
-        /// Bits 4-7 - Submapper number
-        /// </remarks>
-        public byte MapperMSBSubmapper { get; set; }
+        #region Byte 8
 
         /// <summary>
-        /// PRG-ROM/CHR-ROM size MSB
+        /// Mapper MSB bits 8-11
         /// </summary>
-        /// <remarks>
-        /// Bits 0-3 - PRG-ROM size MSB
-        /// Bits 4-7 - CHR-ROM size MSB
-        /// </remarks>
-        public byte PRGCHRMSB { get; set; }
+        /// <remarks>Byte 8, Bits 0-3</remarks>
+        public byte MapperMSB { get; set; }
 
         /// <summary>
-        /// PRG-RAM/EEPROM size
+        /// Submapper
+        /// </summary>
+        /// <remarks>Byte 8, Bits 4-7</remarks>
+        public byte Submapper { get; set; }
+
+        #endregion
+
+        #region Byte 9
+
+        /// <summary>
+        /// PRG-ROM size MSB bits 8-11
+        /// </summary>
+        /// <remarks>Byte 9, Bits 0-3</remarks>
+        public byte PRGROMSizeMSB { get; set; }
+
+        /// <summary>
+        /// CHR-ROM size MSB bits 8-11
+        /// </summary>
+        /// <remarks>Byte 9, Bits 4-7</remarks>
+        public byte CHRROMSizeMSB { get; set; }
+
+        #endregion
+
+        #region Byte 10
+
+        /// <summary>
+        /// PRG-RAM (volatile) shift count
         /// </summary>
         /// <remarks>
-        /// Bits 0-3 - PRG-RAM (volatile) shift count
-        /// Bits 4-7 - PRG-NVRAM/EEPROM (non-volatile) shift count
+        /// Byte 10, Bits 0-3
         ///
-        /// If the shift count is zero, there is no CHR-(NV)RAM.
+        /// If the shift count is zero, there is no RAM.
         /// If the shift count is non-zero, the actual size is
         /// "64 << shift count" bytes, i.e. 8192 bytes for a shift count of 7.
         /// </remarks>
-        public byte PRGRAMEEPROMSize { get; set; }
+        public byte PRGRAMShiftCount { get; set; }
 
         /// <summary>
-        /// CHR-RAM size
+        /// PRG-NVRAM/EEPROM (non-volatile) shift count
         /// </summary>
         /// <remarks>
-        /// Bits 0-3 - CHR-RAM size (volatile) shift count
-        /// Bits 4-7 - CHR-NVRAM size (non-volatile) shift count
+        /// Byte 10, Bits 4-7
         ///
-        /// If the shift count is zero, there is no CHR-(NV)RAM.
+        /// If the shift count is zero, there is no NVRAM.
         /// If the shift count is non-zero, the actual size is
         /// "64 << shift count" bytes, i.e. 8192 bytes for a shift count of 7.
         /// </remarks>
-        public byte CHRRAMSize { get; set; }
+        public byte PRGNVRAMEEPROMShiftCount { get; set; }
+
+        #endregion
+
+        #region Byte 11
+
+        /// <summary>
+        /// CHR-RAM size (volatile) shift count
+        /// </summary>
+        /// <remarks>
+        /// Byte 11, Bits 0-3
+        ///
+        /// If the shift count is zero, there is no RAM.
+        /// If the shift count is non-zero, the actual size is
+        /// "64 << shift count" bytes, i.e. 8192 bytes for a shift count of 7.
+        /// </remarks>
+        public byte CHRRAMShiftCount { get; set; }
+
+        /// <summary>
+        /// CHR-NVRAM size (non-volatile) shift count
+        /// </summary>
+        /// <remarks>
+        /// Byte 11, Bits 4-7
+        ///
+        /// If the shift count is zero, there is no NVRAM.
+        /// If the shift count is non-zero, the actual size is
+        /// "64 << shift count" bytes, i.e. 8192 bytes for a shift count of 7.
+        /// </remarks>
+        public byte CHRNVRAMShiftCount { get; set; }
+
+        #endregion
 
         /// <summary>
         /// CPU/PPU timing mode
diff --git a/SabreTools.Serialization/Readers/NESCart.cs b/SabreTools.Serialization/Readers/NESCart.cs
index cc513d7b..dcdd3404 100644
--- a/SabreTools.Serialization/Readers/NESCart.cs
+++ b/SabreTools.Serialization/Readers/NESCart.cs
@@ -44,12 +44,12 @@ namespace SabreTools.Serialization.Readers
                 int chrRomSize = cart.Header.CHRROMSize * 8192;
                 if (cart.Header is Header2 header2)
                 {
-                    byte msb = (byte)(header2.PRGCHRMSB & 0x0F);
-                    ushort extendedSize = (ushort)((msb << 8) | header.PRGROMSize);
+                    ushort extendedSize = (ushort)((header2.PRGROMSizeMSB << 8)
+                        | header.PRGROMSize);
                     prgRomSize = extendedSize * 16384;
 
-                    msb = (byte)(header2.PRGCHRMSB >> 4);
-                    extendedSize = (ushort)((msb << 8) | header.CHRROMSize);
+                    extendedSize = (ushort)((header2.CHRROMSizeMSB << 8)
+                        | header.CHRROMSize);
                     chrRomSize = extendedSize * 8192;
                 }
 
@@ -114,22 +114,38 @@ namespace SabreTools.Serialization.Readers
                 obj.PRGROMSize = prgRomSize;
                 obj.CHRROMSize = chrRomSize;
 
-                // Flag 6
+                // Byte 6
                 obj.NametableArrangement = nametableArrangement;
                 obj.BatteryBackedPRGRAM = batteryBackedPrgRam;
                 obj.TrainerPresent = trainerPresent;
                 obj.AlternativeNametableLayout = alternativeNametableLayout;
                 obj.MapperLowerNibble = mapperLowerNibble;
 
-                // Flag 7
+                // Byte 7
                 obj.ConsoleType = consoleType;
                 obj.NES20 = nes20;
                 obj.MapperUpperNibble = mapperUpperNibble;
 
-                obj.MapperMSBSubmapper = data.ReadByteValue();
-                obj.PRGCHRMSB = data.ReadByteValue();
-                obj.PRGRAMEEPROMSize = data.ReadByteValue();
-                obj.CHRRAMSize = data.ReadByteValue();
+                // Byte 8
+                byte byte8 = data.ReadByteValue();
+                obj.MapperMSB = (byte)(byte8 & 0x0F);
+                obj.Submapper = (byte)((byte8 >> 4) & 0x0F);
+
+                // Byte 9
+                byte byte9 = data.ReadByteValue();
+                obj.PRGROMSizeMSB = (byte)(byte9 & 0x0F);
+                obj.CHRROMSizeMSB = (byte)((byte9 >> 4) & 0x0F);
+
+                // Byte 10
+                byte byte10 = data.ReadByteValue();
+                obj.PRGRAMShiftCount = (byte)(byte10 & 0x0F);
+                obj.PRGNVRAMEEPROMShiftCount = (byte)((byte10 >> 4) & 0x0F);
+
+                // Byte 11
+                byte byte11 = data.ReadByteValue();
+                obj.CHRRAMShiftCount = (byte)(byte11 & 0x0F);
+                obj.CHRNVRAMShiftCount = (byte)((byte11 >> 4) & 0x0F);
+
                 obj.CPUPPUTiming = (CPUPPUTiming)data.ReadByteValue();
                 obj.ExtendedSystemType = data.ReadByteValue();
                 obj.MiscellaneousROMs = data.ReadByteValue();
diff --git a/SabreTools.Serialization/Wrappers/NESCart.Printing.cs b/SabreTools.Serialization/Wrappers/NESCart.Printing.cs
index 40a6eeed..a00bb8d2 100644
--- a/SabreTools.Serialization/Wrappers/NESCart.Printing.cs
+++ b/SabreTools.Serialization/Wrappers/NESCart.Printing.cs
@@ -124,47 +124,39 @@ namespace SabreTools.Serialization.Wrappers
             else if (header is Header2 header2)
             {
                 // Byte 8
-                byte mapperMsb = (byte)(header2.MapperMSBSubmapper & 0x0F);
-                ushort extendedMapperNumber = (ushort)((mapperMsb << 8)
+                ushort extendedMapperNumber = (ushort)((header2.MapperMSB << 8)
                     | (byte)((header.MapperUpperNibble << 4)
                     | header.MapperLowerNibble));
-                byte submapperNumber = (byte)(header2.MapperMSBSubmapper >> 4);
 
-                builder.AppendLine(mapperMsb, "  Mapper MSB");
+                builder.AppendLine(header2.MapperMSB, "  Mapper MSB");
                 builder.AppendLine(extendedMapperNumber, "  Extended mapper number");
-                builder.AppendLine(submapperNumber, "  Submapper number");
+                builder.AppendLine(header2.Submapper, "  Submapper");
 
                 // Byte 9
-                byte prgRomMsb = (byte)(header2.PRGCHRMSB & 0x0F);
-                ushort extendedPrgRomSize = (ushort)((prgRomMsb << 8) | header.PRGROMSize);
-                byte chrRomMsb = (byte)(header2.PRGCHRMSB >> 4);
-                ushort extendedChrRomSize = (ushort)((chrRomMsb << 8) | header.CHRROMSize);
+                ushort extendedPrgRomSize = (ushort)((header2.PRGROMSizeMSB << 8) | header.PRGROMSize);
+                ushort extendedChrRomSize = (ushort)((header2.CHRROMSizeMSB << 8) | header.CHRROMSize);
 
-                builder.AppendLine(prgRomMsb, "  PRG-ROM size MSB");
+                builder.AppendLine(header2.PRGROMSizeMSB, "  PRG-ROM size MSB");
                 builder.AppendLine(extendedPrgRomSize, "  Extended PRG-ROM size");
-                builder.AppendLine(chrRomMsb, "  CHR-ROM size MSB");
+                builder.AppendLine(header2.CHRROMSizeMSB, "  CHR-ROM size MSB");
                 builder.AppendLine(extendedChrRomSize, "  Extended CHR-ROM size");
 
                 // Byte 10
-                byte prgRamShiftCount = (byte)(header2.PRGRAMEEPROMSize & 0x0F);
-                int prgRamSize = prgRamShiftCount > 0 ? 64 << prgRamShiftCount : 0;
-                byte eepromShiftCount = (byte)(header2.PRGRAMEEPROMSize >> 4);
-                int eepromSize = eepromShiftCount > 0 ? 64 << eepromShiftCount : 0;
+                int prgRamSize = header2.PRGRAMShiftCount > 0 ? 64 << header2.PRGRAMShiftCount : 0;
+                int eepromSize = header2.PRGNVRAMEEPROMShiftCount > 0 ? 64 << header2.PRGNVRAMEEPROMShiftCount : 0;
 
-                builder.AppendLine(prgRamShiftCount, "  PRG-RAM shift count");
+                builder.AppendLine(header2.PRGRAMShiftCount, "  PRG-RAM shift count");
                 builder.AppendLine(prgRamSize, "  PRG-RAM size");
-                builder.AppendLine(eepromShiftCount, "  PRG-NVRAM/EEPROM shift count");
+                builder.AppendLine(header2.PRGNVRAMEEPROMShiftCount, "  PRG-NVRAM/EEPROM shift count");
                 builder.AppendLine(eepromSize, "  PRG-NVRAM/EEPROM size");
 
                 // Byte 11
-                byte chrRamShiftCount = (byte)(header2.CHRRAMSize & 0x0F);
-                int chrRamSize = chrRamShiftCount > 0 ? 64 << chrRamShiftCount : 0;
-                byte chrNvramShiftCount = (byte)(header2.CHRRAMSize >> 4);
-                int chrNvramSize = chrNvramShiftCount > 0 ? 64 << chrNvramShiftCount : 0;
+                int chrRamSize = header2.CHRRAMShiftCount > 0 ? 64 << header2.CHRRAMShiftCount : 0;
+                int chrNvramSize = header2.CHRNVRAMShiftCount > 0 ? 64 << header2.CHRNVRAMShiftCount : 0;
 
-                builder.AppendLine(chrRamShiftCount, "  CHR-RAM shift count");
+                builder.AppendLine(header2.CHRRAMShiftCount, "  CHR-RAM shift count");
                 builder.AppendLine(chrRamSize, "  CHR-RAM size");
-                builder.AppendLine(chrNvramShiftCount, "  CHR-NVRAM shift count");
+                builder.AppendLine(header2.CHRNVRAMShiftCount, "  CHR-NVRAM shift count");
                 builder.AppendLine(chrNvramSize, "  CHR-NVRAM size");
 
                 // Byte 12
diff --git a/SabreTools.Serialization/Wrappers/NESCart.cs b/SabreTools.Serialization/Wrappers/NESCart.cs
index d7046889..1f3ed44e 100644
--- a/SabreTools.Serialization/Wrappers/NESCart.cs
+++ b/SabreTools.Serialization/Wrappers/NESCart.cs
@@ -42,7 +42,7 @@ namespace SabreTools.Serialization.Wrappers
 
                 int chrRomSize = Header.CHRROMSize * 8192;
                 if (Header is Header2 header2)
-                    chrRomSize = ((header2.PRGCHRMSB >> 4) << 8) | chrRomSize;
+                    chrRomSize = (header2.CHRROMSizeMSB << 8) | chrRomSize;
 
                 return chrRomSize;
             }
@@ -65,7 +65,7 @@ namespace SabreTools.Serialization.Wrappers
 
                 int mapperNumber = (Header.MapperUpperNibble << 4) | Header.MapperLowerNibble;
                 if (Header is Header2 header2)
-                    mapperNumber = ((header2.MapperMSBSubmapper & 0x0F) << 8) | mapperNumber;
+                    mapperNumber = (header2.MapperMSB << 8) | mapperNumber;
 
                 return mapperNumber;
             }
@@ -90,18 +90,11 @@ namespace SabreTools.Serialization.Wrappers
                     return 0;
 
                 if (Header is Header1 header1)
-                {
                     return header1.PRGRAMSize > 0 ? header1.PRGRAMSize * 8192 : 8192;
-                }
                 else if (Header is Header2 header2)
-                {
-                    byte shift = (byte)(header2.PRGRAMEEPROMSize & 0x0F);
-                    return shift > 0 ? 64 << shift : 0;
-                }
+                    return header2.PRGRAMShiftCount > 0 ? 64 << header2.PRGRAMShiftCount : 0;
                 else
-                {
                     return 0;
-                }
             }
         }
 
@@ -119,7 +112,7 @@ namespace SabreTools.Serialization.Wrappers
 
                 int prgRomSize = Header.PRGROMSize * 16384;
                 if (Header is Header2 header2)
-                    prgRomSize = ((header2.PRGCHRMSB & 0x0F) << 8) | prgRomSize;
+                    prgRomSize = (header2.PRGROMSizeMSB << 8) | prgRomSize;
 
                 return prgRomSize;
             }
@@ -219,8 +212,7 @@ namespace SabreTools.Serialization.Wrappers
                 if (Header is null || Header is not Header2 header2)
                     return 0;
 
-                byte shift = (byte)(header2.CHRRAMSize >> 4);
-                return shift > 0 ? 64 << shift : 0;
+                return header2.CHRNVRAMShiftCount > 0 ? 64 << header2.CHRNVRAMShiftCount : 0;
             }
         }
 
@@ -236,8 +228,7 @@ namespace SabreTools.Serialization.Wrappers
                 if (Header is null || Header is not Header2 header2)
                     return 0;
 
-                byte shift = (byte)(header2.CHRRAMSize & 0x0F);
-                return shift > 0 ? 64 << shift : 0;
+                return header2.CHRRAMShiftCount > 0 ? 64 << header2.CHRRAMShiftCount : 0;
             }
         }
 
@@ -322,8 +313,7 @@ namespace SabreTools.Serialization.Wrappers
                 if (Header is null || Header is not Header2 header2)
                     return 0;
 
-                byte shift = (byte)(header2.PRGRAMEEPROMSize >> 4);
-                return shift > 0 ? 64 << shift : 0;
+                return header2.PRGNVRAMEEPROMShiftCount > 0 ? 64 << header2.PRGNVRAMEEPROMShiftCount : 0;
             }
         }
 
@@ -339,7 +329,7 @@ namespace SabreTools.Serialization.Wrappers
                 if (Header is null || Header is not Header2 header2)
                     return 0;
 
-                return header2.MapperMSBSubmapper >> 4;
+                return header2.Submapper;
             }
         }